Process of producing asphaltic paving composition.



UNITED STATES Patented November 3, 1903.

PATENT OFFICE.

JOSEPH HAY AMIES, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO AMIES ASPHALT COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A

CORPORATION.

PROCESS OF PRODUCING ASPHALTIC PAVING COMPOSITION.

SPECIFICATION forming part of Letters Patent No. 743,0 November 1903 Application filed September 29, 1902. Serial No. 125,322. ((No specimens.)

To whom it may concern:

Be it known that I, J osnrn HAY AMIES, a

citizen of the United States, residing at Phil-. adelphia, in the county of Philadelphia and 5 State of Pennsylvania, have invented certain new and useful Improvements in Processes of Producing Asphaltic Paving Composition;

and I do declare the following to be a 'full,

clear, and exact description of the invention, [0 such as will enable others skilled in the art to which it appertains to make and use the same.

work.

The object of the invention is to provide a bituminous concrete composition of high. quality and endurance,to efiecta great saving in cost of manufacture, and to provide a com-I position which can be conveniently prepared for use at the place where the work of pavingi or roofing is to be done. The present method of sheet-asphalt pave-i ment-surfacingrequires the combination of; sand and asphalt in a highly-heated condi-i tion, the sand being heated to a temperature of about 480 Fahrenheit and the asphalt reduced to a liquid at a temperature of about;

0 340 Fahrenheit. At these temperatures the two are combined in a mixing-machine. The result is that the mastic thus produced is always burned, and therefore its wearing qualities are greatly decreased. Thenecessity of using such very high temperatures in order to economically mix the sand and as phaltic liquid and to deliver the mastic in a friable condition to the rakers at a distant point where the street is in process of cono struction prevents the laying of a highly-endurable pavement, and notwithstanding the high temperatures employed over ten per cent. of the mastic is lost by cooling during its transit from the mixing-plant to the rakersq Furthermore, the high temperatures at which the parts of the mastic composition are combined render it obligatory to employ ex-j tensive machinery and furnaces in station-I ary plants located necessarily in large citiesj amount of mastic ordinarily lost by cooling.

a thick paste.

where large contracts can be obtained. Costly railroad paving plants have been used to enable ork to be done in places unprovided with stationary plants; but such have been practically abandoned on account of high transportation and sidingv charges. In the case of either stationary or railroad plants it is practically impossible on account of the heavy expenses referred to to profitably lay sheet-asphalt pavements in small cities, towns, and places where only small contracts can be secured. My invention obviates all these objections and enables small contract work to be profitably done and at the same time produces a better pavement and saves the 5 In carrying my invention into practice I first reduce the asphalt to a powder and then mix two parts of powdered asphalt with one part of crude petroleum-oil. This will make This paste is placed in barrels carefully closed to prevent the evaporation of the volatile elements of the oil. In these packages it is finally delivered to the places Where the street-surfaces are being laid; but I may, if desired, send the asphalt in bags to the point where construction is going on and there mix it with the oil. The paste thus formed is placed in a suitable receptacle and heat applied thereto until the resulting liquid is raised to a temperature of about 180 Fahrenheit. At this heat a very thin liquid results, and before too great a portion of the volatile elements of the oil are driven off said liquid is mixed with sand which has been previously heated to a temperature of about 85 215 Fahrenheit. The liquid asphalt, sand, 7 and other materials used to make the complete composition are then combined by being stirred in due proportions on a mixing-board by hand or in a mixing-machine by power. In either case the mastic thus manufactured is delivered to the rakers close at hand.

Under the action of the oil the ground asphalt becomes perfectly macerated or softened, and as the oil is very sensitive to heat but a comparatively low temperature of heat is required to dissolve the macerated asphalt to a thin liquid. As under the efiects of the heat the volatile elements of the liquid begin at an early stage to be released, the macerated asphalt is only heated in single batch quantities at a time, and it is taken as soon as dissolved and mixed with the hot sand, which is also heated in' batch quantities to secure rapid warming. At the low temperatures at which the macerated asphalt and sand are combined the resulting mastic will be perfectly friable, owing to the effect of the oil, and the rakers are thereby enabled to work it to a smooth face, in which condition it will remain until it has cooled off sufficiently to admit of effective tamping and rolling, at which time the volatile elements of the oil will have been driven off by the heat employed and the facing will perfectly cement and unite and become in a few hours sufficiently hard for practical purposes. It will thus be readily seen that by my process of making the mastic and performing the mixing operation in close proximity to the point where the work is being done the mastic can be made and laid in'severe winter weather, because the heat employed, though comparative low,will keep the composition sufficiently friable for the work during the limited time required to convey the mastic to the point of use. With the ordinary process of manufacture this operation of laying the mastic in severe winter weather is impracticablein nearly all cases, because of the long hauls from distant plants. Furthermore,,the simple form of apparatus required in my process to heat the asphaltic liquid and sand to the low temperatures which I am enabled to employ can be conveniently used at the street or road side where the work is being done and can be easily moved from place to place by hand or,

horse power where railroad facilities are not convenient, thereby enabling the work to be done at a minimum expense in all localities:

My process possesses the additional advantage of providing a better and more endnrable mastic and of effecting a considerable saving,

of material, as the quality of the asphalt is not impaired by burning and none of the mastic is lost by cooling, as in the ordinary process. Hence the necessity of building and maintaining extensive plants will give place as the result of my method to a simple transportable apparatus which can be provided at low cost, and owing to this fact and to the low temperatures at which I am enabled to work the cost of laying sheet-asphalt pave-- the street-facing will remain too soft for practical purposes, or if the mastic be allowed to stand long enough for the complete volatilization of the light oils in the asphaltic liquid it will become too cold to properly and strongly cement. On the other hand, I have ascertained by practice that if less than one part of oil to two of the powdered asphalt be used the dissolved liquid will be too stiff to combine with the hot sand in a friable condition, so that the resulting mastic will be lumpy and prevent perfect facing and cementing; but it may be found desirable under some conditions tosomewhat increase or decrease the amount of crude oil used, and hence Ido not wish to restrict myself to precisely the quantity named; nor do Iwish to confine myself to the exact degree of heat mentioned for the sand, though I have found that the temperatures named for both the sand and asphaltic liquid give the best results.

I am not compelled to mix the crude oil previously with the powdered asphalt, as I may do this at the place and time at which the street-surface is being constructed, or I may place the crudeoil separately into the heating-receptacle and when it is sufficiently heated sprinkle the powdered asphalt therein and vigorously'stir and agitate the two while doing so, and thus obtain my asphaltic liquid; but I prefer to make the cold paste as described, because I have found that the crude oil will macerate the ground asphalt and become practically homogeneous therewith when it remains associated with the asphalt for a time, and when heat is applied to the mixture the asphalt will much more readily dissolve, owing to the marcerating effect of the oil; but where it becomes more convenient I may adopt either or both of the ways above explained.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. The herein-described process of producing a composition for paving, &c., which consists in first subjecting powdered asphalt to the macerating efiect of crude petroleum-oil for a sufficient period to form a paste, and then reducing the paste to a liquid condition by the action of heat.

2. The-herein-described process of producing a composition for paving, &c., which consists in first subjecting powdered asphalt to the macerating efifect of crude petroleum-oil for a sufficient period to form a paste, reducing the paste to a liquid condition by the action of heat, and then mixing said liquid with heated sand.

3. The herein-described process of making a bituminous composition for paving, consisting in reducing asphalt to powder, mixing two parts of the powdered asphalt with one part of crude oil to form a paste, subjecting the paste to heat to liqnefy the same, and combining the liquefied mixture with hot sand, substantially as described.

4. The herein-described process of manufacturing bituminous concrete, which consists IfO of first reducing asphalt to powder, then mixing two measures of the powdered asphalt with one measure of crude petroleu m-oil, then allowing the oil to macerate the asphalt to form a paste, heating the paste and bringing the resulting liquid to a temperature of about 180 Fahrenheit, then mixing the asphaltic liquid thus procured with sand which has been previously heated to'a temperature of about 215 Fahrenheit, substantially as described.

5. The herein-described process of producing a bituminous paving composition which consists in combining asphalt in a finely-divided condition with crude petroleumoil, allowing the oil to act under normal tempera ture upon the asphalt to reduce the same to a macerated condition, thus forming a cold paste, and reducing the cold paste to a liquid by a low degree of heat for use, substantially as described.

6. The herein-described process of producingabituminous paving composition designed for immediate use, which consists in reducing asphalt to a divided state, combining same with crude petroleum-oil, allowing the oil to macerate the asphalt and form therewith a paste, reducing a batch quantity of the paste to a liquid condition under a low degree of heat and at a point in proximity to the point where the paving is being laid, simultaneously heating sand, and combining a suitable proportion of the heated sand with the batch ing a bituminous composition for paving, 4

which consists in subjecting powdered asphalt to the maceratin g effect of petroleum-oil, heating a batch quantity of the resulting paste to a liquid condition, and mixing the liquid with a batch quantity of hot sand for immediateuse.

8. The herein-described process of producing a composition for paving, which consists in reducing a suitable quantity of asphalt to powder, mixing the same with a suitable quantity of crude petroleum-oil by agitation, sealing the vessel so as to confine the volatile vapors and allow the oil to macerate the asphalt to produce a paste, heating a batch quantity of the paste to a liquid condition for immediate use, and incorporating the same with a batch quantity of hot sand, forming a friable mastic adapted to harden by the evaporation of the volatile constituents of the oil under the action of the employed heat, substantially as described.

In testimony whereof I have hereunto set my hand in presence of two subscribing wit- HOSSGS.

JOSEPH HAY AMIES. Witnesses:

JAMES P. PETIT, FLETCHER W. STITES. 

